alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET HUNTING Suspicious Proxifier DL (non-browser observed in maldoc campaigns)"; flow:established,to_server; http.uri; content:"/distr/Proxifier"; nocase; startswith; fast_pattern; http.host; content:"proxifier.com"; endswith; http.header_names; to_lowercase; content:!"|0d 0a|user-agent|0d 0a|"; nocase; content:!"|0d 0a|referer|0d 0a|"; content:!"|0d 0a|accept-"; content:!"cookie|0d 0a|"; reference:md5,2a0728a6edab6921520a93e10a86d4b2; classtype:trojan-activity; sid:2023138; rev:6; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2016_08_26, deployment Perimeter, performance_impact Low, confidence Medium, signature_severity Major, tag MalDoc, updated_at 2024_05_01;)